% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@PHDTHESIS{Poley:402646,
author = {Poley, Anne-Luise},
othercontributors = {Bloch, Ingo and Moenig, Klaus},
title = {{S}tudies of adhesives and metal contacts on silicon strip
sensors for the {ATLAS} {I}nner {T}racker},
school = {Humboldt-Universität zu Berlin},
type = {Dissertation},
address = {Hamburg},
publisher = {Verlag Deutsches Elektronen-Synchrotron},
reportid = {PUBDB-2018-01870, DESY-THESIS-2018-011},
series = {DESY-THESIS},
pages = {260},
year = {2018},
note = {Dissertation, Humboldt-Universität zu Berlin, 2018},
abstract = {This thesis presents studies investigating the use of
adhesives on the active area of silicon strip sensors for
the construction of silicon strip detector modules for the
ATLAS Phase-II Upgrade. 60 ATLAS07 miniature sensors were
tested using three UV cure glues in comparison with the
current baseline glue (a non-conductive epoxy).The impact of
irradiation on the chemical composition of all adhesives
under investigation was studied using three standard methods
for chemical analysis: quadrupole time-of-flight mass
spectroscopy, gel permeability chromatography and gas
chromatography combined with mass spectrometry (GC-MS).
GC-MS analyses of glue sample extracts before and after
irradiation showed molecule cross-linking and broken
chemical bonds to different extents and allowed to quantify
the radiation hardness of the adhesives under
investigation.Probe station measurements were used to
investigate electrical characteristics of sensors partially
covered with adhesives in comparison with sensors without
adhesives. Leakage current, bulk capacitance, inter-strip
capacitance and surface resistance were measured before and
after gluing, after irradiation and after temperature
cycling. The presence of glue on the active sensor area was
found to increase the sensor leakage current and inter-strip
capacitance and frequently led to early sensor breakdowns.
Temperature cycling and irradiations reduced adverse effects
due to glue to a small noise difference between sensors with
and without glue.Charge collection efficiency measurements
in a $\beta$-source setup were used to study the influence
of adhesives on the silicon bulk. All sensors under
investigation showed equivalent charge collection
efficiencies for sensors with and without glue, as well as
signal-to-noise ratios above the required minimum of ten for
the foreseen bias voltage. Before irradiation, sensors with
glue showed increased cluster sizes, which could be
attributed to fluorescence effects inside the glue using
testbeam measurements.During testbeam studies, sensor strips
were found to respond inhomogeneously in bond pad regions.
Follow-up measurements confirmed that the presence of bond
pads affects the electric field within a sensor and leads to
additional charge being collected around bond pads. As a
result of these findings, the sensor bond pad layout was
modified in order to minimise reduced tracking resolution
caused by shifted strip responses.},
cin = {ATLAS},
cid = {I:(DE-H253)ATLAS-20120731},
pnm = {632 - Detector technology and systems (POF3-632)},
pid = {G:(DE-HGF)POF3-632},
experiment = {EXP:(DE-H253)LHC-Exp-ATLAS-20150101},
typ = {PUB:(DE-HGF)3 / PUB:(DE-HGF)29 / PUB:(DE-HGF)11},
doi = {10.3204/PUBDB-2018-01870},
url = {https://bib-pubdb1.desy.de/record/402646},
}